About geospatial dataset descriptions

A dataset is a particular organised collection of data with a common
theme. A dataset description is a concise document that describes a
dataset.

The dataset description document is well-defined and structured, using
elements of metadata (data about data). It is analogous to a card in the
catalogue of your local library which describes the books and gives enough
information to know what the book is called, its unique number, how and
where to find it. These details are metadata - bibliographic elements such
as Author, Title, Abstract.

This document outlines the management of geospatial dataset descriptions
using Eco Companion.

In the context of the Eco Companion catalogue, a dataset is any
organised collection of data or information that has a common theme. It
also has, among its attributes, a reference to a location in earth-centred
space.

A dataset might be a list of objects, a digital map, records of
geological borehole samples, a collection of photographs at a certain
location or of a certain subject, a database comprising records of
pollution sites, a scientific report, a listing of results from a school
project.

A dataset need not only be in digital form. A paper publication, or
report, or collection of maps are also datasets.

Dataset descriptions concisely describe collections of data that are
available free-of-charge or for sale.

As a member of the Eco Companion service you can maintain descriptions
of datasets for which you are the custodian.

If you choose to publish those dataset descriptions, then they will be
available for searching through the Eco Companion catalogue. This then
enables Internet searchers to discover such datasets that may meet their
needs.

There are two methods to prepare your dataset description documents:

use the Eco Companion "Edit dataset description"
facility

Online forms guide you through the process.

or, place your own metadata document at another Internet server

Prepare your own metadata document and ask our
ANZMP geospatial metadata parser to
retrieve it across the network. Batch processing for metadata
collections.

Metadata is data about data. A dataset description is metadata,
describing the data, but is not the actual data itself.

The dataset description document is well-defined and structured using
elements of metadata. It is analogous to a card in the catalogue of your
local library which describes the books and gives enough information to
know what the book is called, its unique number, how and where to find it.
These details are metadata - bibliographic elements such as Author, Title,
Abstract. [see glossary]

Geospatial dataset descriptions are composed of well-defined metadata
elements which have a specific structure and order. The dataset
descriptions are maintained as documents in the Standard Generalised
Markup Language (SGML). The Document Type Definition
(DTD) defines the allowed structure and elements that
must comprise a dataset description. This DTD then facilitates automatic
and consistent processing of dataset descriptions.

At its very basic form, the Structured Generalized Markup Language
(SGML) describes particular elements of text with easily recognisable
nametags in opening and closing pairs. These elements can be parents and
children, thus describing a hierarchical, structured relationship between
the elements of a document.

To ensure that all dataset descriptions are of a consistent type, the
Document Type Definition (DTD) defines the metadata elements and their
order and structure. The DTD is "used to automatically process a
document ... and check that all of the elements required for that document
are indeed present and correctly ordered"[from
A Gentle Introduction to SGML].

This insistence on a uniform document type means that the SGML dataset
description documents can be readily transferred between information
systems (as SGML is independent of vendors, platforms, and software). The
documents can be consistently processed to ensure that they are valid and
that search facilities can rely on certain elements (such as the
geographic extents and the keywords). The DTD is a vital component of the
SGML document management solution. See further
explanation and the
glossary.

The Australia New Zealand Land Information Council (ANZLIC)
has released the ANZMETA XML DTD to define geographic dataset descriptions in
Australia and New Zealand. The ANZMETA DTD and supporting documentation
can be found at
http://www.auslig.gov.au/anzmeta/During 2000-2001 the ANZMETA DTD is expected to evolve to be the Australian profile of the
ISO metadata (ISO 19115).

To ensure consistent document production, the DTD specifies that there
must be one and only one TITLE element, and that the CUSTODIAN and
JURISDICTION elements must immediately follow the TITLE and be contained
in the ORIGINATOR element.